deliverable d2.5 decision grid for best approach in terms of … · 2017-02-22 · approach (spr)...

CONTRACT NB SD/TE/02A

FRAC-WECO

Flux-based Risk Assessment of the impact of Contaminants

on Water resources and ECOsystems

Programme: La Science pour un Développement Durable

Programma: Wetenschap voor een Duurzame Ontwikkeling

Deliverable D2.5

Decision grid for best approach in terms of modelling

concepts/contaminants

Responsible D.Caterina (ULg HG), Michael Haberman (ULg HG)

Contributors S. Brouyère, A.Dassargues

Corresponding authors: [email protected], Tel: +32 4 366 92 62

[email protected], Tel: +32 4 366 23 77

[email protected], Tel: +32 4 366 23 76

Due date: April 2008

FRAC-WECO Deliverable D2.5 1

Contents

1.� GENERAL CONTEXT ......................................................................................... 3�

2.� INTRODUCTION TO RISK ASSESSMENT CONCEPTS ................................... 6�

2.1.� Introduction ............................................................................................................................... 6�

2.1.1� Definition ............................................................................................................................................. 6�

2.1.2� Various types of risk assessment .......................................................................................................... 7�

2.1.3� Limitations of risk assessment ............................................................................................................. 7�

2.2.� Methodologies for risk assessment of contaminated sites ................................................. 8�

2.2.1� Introduction .......................................................................................................................................... 8�

2.2.2� Components of risk assessment ........................................................................................................... 9�

2.2.3� Framework of risk assessment ........................................................................................................... 10�

2.2.4� Screening and guideline values .......................................................................................................... 13�

2.3.� Methodologies for risk assessment of contaminated megasites ..................................... 17�

2.3.1� Introduction........................................................................................................................................ 17�

2.3.2� Superfund ........................................................................................................................................... 18�

2.3.3� INCORE (INtegrated COncept for groundwater REmediation) ........................................................ 21�

2.3.4� WELCOME (Water, Environment and Landscape management at COntaminated MEgasites)......... 22�

2.3.5� What megasite approach for FRACO-WECO .................................................................................... 25�

3.� SYNTHESIS OF RISK ASSESSMENT TOOLS ................................................ 27�

3.1.� Introduction ............................................................................................................................. 27�

3.2.� Literature review of Decision Support Tools ....................................................................... 27�

3.3.� Groundwater modelling ......................................................................................................... 30�

4.� CONCLUSIONS AND RECOMMANDATIONS ................................................. 32�

5.� REFERENCES .................................................................................................. 34�

ANNEXES ................................................................................................................ 39�

Annex 1: Definitions ............................................................................................................................ 40�

Annex 2: International approaches to ecological risk assessment ............................................... 42�


Annex 3: INCORE flow chart .............................................................................................................. 43�

Annex 4: Tools developed in the scope of The WELCOME project ............................................... 44�

Annex 5: Fact sheets on the decision support and modelling tools ............................................. 45�

List of illustrations

Figure 1 : Complexity level as regards with tiers of the risk assessment process ..................... 9�

Figure 2 : Framework of risk assessment ................................................................................. 12�

Figure 3 : Graphical representation of generic value types (R0, R1, R2, R3) and approaches

taken in different countries ....................................................................................................... 14�

Figure 4 : INCORE cyclic approach ........................................................................................ 21�

List of tables

Table 1 : Types of land contamination ....................................................................................... 3�

Table 2 : S/G values within the soil policy framework in different countries ......................... 16�

Table 3 : Summary of DSTs ..................................................................................................... 29�


1. General context

For many years, Belgium as well as many other industrialised countries throughout the world

(EU, USA, etc.), have become aware of problems related to contamination issues. Many

industrial and economical activities are the main causes of the presence of contaminants in the

environment, especially due to development of industries without environmental

considerations or constraints. In fact, economical activities (industries, agriculture, etc.) emit a

large quantity of toxic substances (chlorinated solvents, pesticides, etc.) in the environment

and these compounds can therefore be found in the air, soil, surface water and groundwater.

This general contamination may cause many damages on human health, ecosystems and

natural resources.

According to the European Environment Agency (EEA, 2007), polluting activities have been

carried out on 3 millions of sites in Europe during these last years, among which 1.8 million

sites are now potentially contaminated. Until now, only 250 000 of them have been clearly

identified but this number could increase in the future with new investigations.

The main sources of contamination may be listed as follows:

Potential sources of land contamination

Industrial

gas works,coal processing,extractive industry, mines, chemical production or use, electroplating, timber reservation, metal production/manufacturing, chemical stores, pesticide formulation, food processing, pulp and paper manufacture, textile production, other industries

Commercial petrol service stations, transport services/maintenance, motor car wrecking, waste, recycling depot/plant

Service sector municipal/industrial landfills, sewage treatment works, fuel depots, energy generating plants, laboratories

Agricultural intensive use of pesticides, aerial spraying operations, pesticide storehouses

Other abandoned dumpsites, abandoned mines, factory or warehouse fire, chemical transport accident

Table 1 : Types of land contamination (adapted from UNEP & al., 2005)

Statistical data from EEA have listed the major pollutants found in soils, among which heavy

metals (for 37.3% of cases) and hydrocarbons (33.7%) constitute the two main categories.

For the specific case of groundwater, hydrocarbons constitute the main types of pollutants,

followed by chlorinated compounds. This study has also shown that 80 000 of industrial sites

have been the subject of decontamination works these last 30 years. So, people have become

more and more aware and informed of risks posed by these sites on the environment and have


become conscious of the necessity to preserve and restore natural resources and ecosystems.

Therefore, these sites have to be managed both from a risk and economical point of view.

To achieve these objectives, one needs:

� efficient methodologies and norms for screening contaminated sites with respect to

contamination types and levels;

� a reliable evaluation of the possible impacts of these sites on the environment, by direct

exposure or by dispersion in the environment, particularly through water resources;

� risk assessment for humans, ecosystems and natural resources and;

� the development of tools and methodologies for evaluating, ranking and optimizing

remediation measures.

Despite the fact that many human and financial efforts have been devoted to these important

objectives, one has to admit that there is nowadays no unified system allowing to hierarchise

methodologies and tools for site screening, risk assessment and remediation optimization.

There have been general accepted concepts and advanced research efforts but the topic is

wide: many contexts, many contaminants and many “targets” and important research works

still have to be performed.

One of the objectives of the FRAC-WECO project is to propose, develop and validate site

screening and risk assessment tools. A first essential step is to provide a relatively detailed

overview of existing methodologies and modelling tools for risk assessment. These tools

should notably assess the appropriate information about fate and transport of contaminants

from the pollutant source through groundwater (i.e. leaching to and transport in the aquifers)

and their possible transformation during their travel allowing thereby assessing their possible

effects and impacts on different receptors, i.e. ecosystems, water resources. Such a modelling

approach may improve the reliability of the assessment in order to help in the decision making

as well as in assessing the costs of a possible contaminated land remediation.

This deliverable constitutes a review of existing approaches for site screening and risk

assessment methodologies and modelling tools. This review aims at identifying those that are

the most appropriate with respect to the general philosophy of the FRAC-WECO project, i.e.

flux-based risk assessment and the considered targets, i.e. water resources and associated

ecosystems.


The document is organised as follows. First, the concepts of risk assessment are discussed and

classical methodological frameworks are presented. Second, several methodologies for the

management of contaminated megasites are described. Third, a synthesis of existing risk

assessment tools is proposed based on a detailed literature review. Finally, a general

discussion is proposed and conclusions are drawn in terms of research directions to be

followed in FRAC-WECO.


2. Introduction to risk assessment concepts

2.1. Introduction

2.1.1 Definition

For few years, risk assessment has become a commonly used approach in environmental

policy (regulators, industries, etc.) because it helps and facilitates decision making for the

management of natural resources and the prevention of damages caused on ecosystems and

human health. A widened knowledge of potential environmental stressors, by identification

and quantification of risks associated with potential threats, and the collaboration of

stakeholders are fundamental to insure the most appropriate decision. Although risk

assessment is central in environmental policy and practice, it is not an easy or well-defined

concept, due notably to different terminologies, approaches and conventional choices taken in

each country or region.

Several definitions, ranging from informal to very formal (mathematical), were already

mentioned by Vlek (1990) and many other authors.

Risk is usually defined as "the chance of disaster" but in the risk assessment process, it is

defined as the combination of “the probability/frequency of occurrence of a defined hazard

and the magnitude of consequences of the occurrence” (Royal Society of London, 1992). The

risks caused by hazards are estimated either quantitatively or qualitatively. Risk is estimated

by likelihood measures of the hazard actually causing harm and severity measures of harm in

terms of impacts to people and environment (effects and threats of an agent on humans and

ecosystems). Risk depends on both the level of toxicity of hazardous agents and on the level

of exposure.

Environmental Risk Assessment (ERA) represents the global term including human health

and ecological risks. ERA involves the examination of risks resulting from natural events

(flooding, extreme weather events, etc.), technology, practices, processes, products, agents

(chemical, biological, etc.) and industrial activities.

It is usually admit that a contaminated site poses a risk only if the following three conditions

are met:

• a source of mobilisable contaminants;


• transfer pathways;

• existence of receptors.

These conditions correspond to the main elements of the Source – Pathway – Receptors

Approach (SPR) which is described in detail for the FRAC-WECO project in deliverable

D12: Methodology for integration of process studies and development of a decisison support

tool.

If one of the three conditions is not met, the contaminated site does not pose an immediate

risk.

2.1.2 Various types of risk assessment

Risk assessment is a relatively complex concept that is not only limited to the assessment of

contaminated lands.

Indeed, it can be used for other purposes, varying from prevention of pollution by new

chemicals to environmental and financial impacts assessment.

ERA can be used in a number of ways:

� Prioritization of risks: according to potential environmental risks, ERA can be used to

establish their relative importance, and thus provides a basis for prioritizing which risks

should be dealt with first;

� Site-specific risk evaluation: ERA can be used to determine the risks associated with a

particular site (CSA, 1997);

� Comparative risk assessment: ERA can be used to compare the relative risks caused by

stressors at different scales;

� Quantification of risks: ERA can be used to quantify the risks in order to establish

appropriate controls and monitoring on these risks (i.e. maximum “acceptable”

concentration).

According to the types of risks and the results of ERA, risks may be managed by elimination,

transfer, retention or reduction to achieve an “acceptable” level of risk.

2.1.3 Limitations of risk assessment

Many organisations in Europe and throughout the world, are actively involved in

environmental risk assessment, developing methodologies and techniques to improve


environmental management tools. Nevertheless, this concept often tends to have a possible

over-reliance in results and generally focuses on parts of a problem rather than on its whole.

Moreover, in contaminated lands, risk assessment is usually not a preventive approach

because the polluting source already exists.

The major difficulties in the use of risk assessment are data availability and uncertainties.

These uncertainties may be listed according to many categories (Wynne, 1972; Shrader-

Frechette, 1996):

� Samples: uncertainties related to measurements accuracy or samples validity;

� Data: interpolation or extrapolation of data;

� Knowledge: insufficient understanding of the topic;

� Models: approximation of the real environment;

� Environment: uncertainties related to the inherent variability of the environment causing

errors in the contaminated lands characterization and;

� Decision theoretic uncertainty: doubt in the choice of decisions based on the type of risks,

contemplated scenarios, cost/benefit analyses, etc.

Risks perception may also play a role in assessing and managing risks because it often

depends on people attitudes and social or cultural values adopted towards hazards. The risk

assessment depends widely on legislative aspects such as environmental standards,

cost/benefit, industrial norms, government policy, etc.

So, it is fundamental to understand the level of uncertainty and to identify the weak points and

limits of the risk assessment at each stage of the process.

2.2. Methodologies for risk assessment of contaminated sites

2.2.1 Introduction

Previously, methodologies used for the remediation of contaminated lands were little based on

risks analysis and assessment. Rehabiliation costs were generally too high to “clean up” the

polluted soils and the process was often dropped (Salt et al., 1995).

For a few years, many countries have changed their policies with regards to remediation

techniques. They tend now to focus more towards a land-use-based approach where risk

assessment is an integrative part of the rehabilitation process (Ferguson et al., 1998).


Furthermore, the type of contaminants, their toxicity, the potential receptors, the political and

social context, are all many important criteria considered in the process. In this perspective, a

Risk Based Land Management (RBLM) concept was developed to help decisions making for

remediation of contaminated lands by assessing the risks and priorities, by considering the

long term effects of contaminants on environment and by evaluating costs and benefits

(Clarinet, 2002). This approach tends to reduce the rehabilitation costs by limiting the number

of treatments applied to the polluted soils. Indeed, it allows to stop the cleaning process as

soon as an “acceptable” level of contamination is achieved, the risks generated by the

remaining part of contaminants being under control.

Different international approaches focusing on ecological risk assessment for land

contamination are presented in Annex 2 (Smith et al., 2005).

2.2.2 Components of risk assessment

Risk assessment of contaminated lands is often based on a causal stress-response model in

which the pollutant is transported from a Source through a known Pathway to a Receptor.

This approach, commonly called SPR, constitutes the basis of risk assessment into which the

FRAC-WECO project fits.

The risk assessment process generally consists of many phases or “tiers” in which different

procedures or concepts are involved and studied. At each tier in the advancement of the

process, the need of data grows, the costs become increasingly important while hoping to

reduce the risks, the assumptions and the uncertainties related to the knowledge of the

problem (Figure 1).

Figure 1 : Complexity level as regards with tiers of the risk assessment process


Risk assessment usually starts with some suspicions about the possible presence of pollutants

in soils or groundwater. This qualitative information - tier 1 - may lead initially to subjective

assessment about environmental risks and sometimes financial risks for people potentially

affected by the polluted sites (Ferguson et al., 1998). In order to be more certain about the

consequences of pollution, investigations may be carried out to establish contamination levels

based on different criteria, i.e. type of contaminants, their toxicity, their concentrations,

potential effects/impacts on environment, risks for human and ecosystems, etc. Pollutant

concentrations measured in soils and groundwater are compared to predetermined guideline

values or quality standards to evaluate whether it is necessary to carry on further

investigations. If the concentrations of contaminants exceed guideline values, more detailed

investigations are required - tier 2. In most countries, the use of these guidelines may serve as

first screening of ecological risks (Ferguson et al., 1998). At each new step in the

advancement of the process - tier n -, the information becomes progressively more

quantitative, through the development of complex models supported by new intensive

investigations of the contaminants of concern, pathways and receptors characteristics, etc.

Each new investigation aims to increase the level of confidence in the results and conclusions

by a better knowledge of the problem while reducing the risks and the associated uncertainties

(Figure 1).

2.2.3 Framework of risk assessment

Although several frameworks for environmental risk assessment and management were

developed throughout the world, most of them are nowadays based on the report “Risk

Assessment in the Federal Government: Managing the Process,” from the US National

Research Council (NRC, 1983). Nevertheless, different criteria such as the political and social

context may lead to differences between countries.

The generalised framework drawn for ERA includes five main steps as illustrated in Figure 2

(NRC, 1983; US EPA, 1998; R. Fairman et al., 1999):

� Problem formulation: general description of the problem with delineation of goals and

objectives. This step is the “foundation” in the process. It is the phase where risk

assessment is defined and the planning for analyzing and characterizing risks is developed

(US EPA 1992/1998). This step provides some information concerning current and

historic land-uses, potential/actual contaminants of concern, potential pathways, potential

receptors, areas of uncertainty. This information allows to describe the system briefly. It is


the step where each element described in the SPR and DPSIR approaches (integrated in

the FRAC-WECO project) are identified ;

� Hazard identification: identification of agents that may cause adverse effects. This step is

often part of the problem formulation (i.e. US EPA), but it may be revisited during the

characterization of effects if new data suggest additional hazards;

� Exposure assessment (characterisation of exposure): estimation of concentrations, doses

and degree of contact of the hazardous agents in question with the environment.

Generally, this phase requires the identification, the characterisation and the quantification

of all sources and stressors and use contaminants fate and transport models for evaluating

the pathways and exposure in groundwater and surface water (relationship between the

contaminants source and the potential pathways, i.e. groundwater, as mentioned in the

SPR approach of the present project);

� Dose-response assessment (characterisation of effects): estimation of the relationship

between exposure (or dose) to a stressor and the incident and severity of an effect on the

environment. This step requires the evaluation of the nature, intensity and time scale of

adverse effects with a causal relation to the stressor and the identification of modes of

action;

� Risk characterisation: evaluation and conclusions. The objective of this step is to collate

and summarise the information obtained during the previous tasks in order to determine

the probability that a risk exists,and its potential magnitude, and to provide the adequate

decisions for risk management. Risk characterisation involves comparing on-site

contaminant concentrations with guideline values (relationship between the pollutants

source and impacts on ecosystems and water resources through the DPSIR approach).


Figure 2 : Framework of risk assessment (adapted from US EPA, 1998)

The risk assessment process is often divided into three main levels (Figure 2). The problem

formulation with hazard identification is generally considered as tier 1. With the analysis for

characterization of exposure and effects, complex modelling tools are necessary to assess

accurately the damages on environment and the risks. This second step is generally the tier 2.

Finally, the tier 3 includes the conclusions of the risk assessment process with risk

characterization in order to help the decision making for a possible contaminated lands

rehabilitation. Each stage in the procedure may be iterated if additional data or analysis is

needed to support the risk management process.

In some countries (notably in UK or New Zeland), risk assessment can be subdivided into

three distinct tiers in which the five key tasks of risk assessment are undertaken. Gathered

information and data are then used to support the risk management decision and to decide

whether it is necessary to proceed to the next tier. In other countries (notably in USA), risk

assessment methods do not explicitly provide a tiered approach but leave the decision to risk

assessors.

If well designed, a tiered approach provides a systematic way of determining what level of

investigation is appropriate for the site of concern, minimizing the number of unnecessary


investigations and allowing a more efficient use of resources. At each tier, if the contaminant

concentrations do not exceed the threshold values, the risk assessment process may be

suspended without proceeding to the next step.

2.2.4 Screening and guideline values

Nowadays, risk assessment is a widely accepted procedure in contaminated land policies to

classify polluted soils. This classification is based on threshold concentration values,

commonly called screening and guideline values (S/G values). Screening values are intended

to screen out sites (or parts of sites) for which risks are considered as being too small to

warrant more detailed investigation. They are generally based on pessimistic exposure

assumptions or rigorous criteria for maximum tolerable risk. Guideline values are used by risk

assessors as generic guidance to provide information on the significance of contaminant

concentrations in soil, groundwater or other media. They may be based on rigorous multi-

pathway probabilistic risk analysis of generic exposure scenarios or on the most basic

screening values..

Although the S/G values are recognized throughout the world, there are some differences

between countries with regards to their roles and definitions. According to the different

phases in the risk assessment and management of contaminated sites (investigations and

decision making process), S/G values may be generally classified as follows (Figure 3):

� Background values (R0): reference level corresponding to unpolluted or non-

anthropogenic conditions. Risks are considered as negligible;

� “Conservative” values (R1): level below which the risk is considered as acceptable.

Above this value, significative risks are more likely to occur and some new considerations

and risk assessment may be required;

� “Realistic” values (R2): for concentrations above these values, the existence of

unacceptable risks is strongly presumed and further investigations are necessary;

� Action/Intervention values (R3): generic values based on acute risks to sensitive receptors.

The measured contaminants concentrations exceed the intervention values, meaning

unacceptable harm or damage. The site remediation becomes a priority.

In general, the R0-type values are established, predicated on “natural” background noise, as

for the R1, R2 and R3-type values, they are calculated by taking into account risks for human

health, ecosystems, etc. In the specific case of groundwater, the R0-type values provide a


value of background concentrations in pollutant without natural geochemical background and

economical activities (agriculture, industries, etc.). R1, R2 and R3-type values are calculated

from ecotoxicological data by evaluating the response of a known pollutant agent on a defined

ecosystem.

The four above-mentioned values may have many functionalities:

� The R0-type values allow differentiating natural and anthropogenic concentrations;

� The R1 and R2-type values inform on the need to perform further investigations and more

detailed risk assessment;

� The R2 and R3-type values are usually used to establish the need for remediation;

In some countries, S/G values may be used as remediation objectives when the remedial

technologies are available at a reasonable cost. In this case, the R0-type values may help to

identify remediation targets constituting negligible risks; the R1 and R2-type values may

classify remediation targets on the basis of acceptable risks related to land-use.

In general, three different approaches can be distinguished in the site assessment process

according to countries (Figure 3):

Figure 3 : Graphical representation of generic value types (R0, R1, R2, R3) and approaches taken in

different countries (Ferguson et al., 1998)

� Type A: based on guideline values (i.e. Denmark, the Netherlands or Italy);


� Type B: based on screening values for a simplified risk assessment (i.e. Austria, Flanders,

Finland, France, Germany, Norway and Switzerland);

� Type C: generally based on guideline values, this approach depends strongly on

characteristics of the investigated site and so, it is fundamental to verify the

appropriateness of considered values before beginning the risk assessment process (i.e.

Greece, Portugal, Sweden and the United Kingdom).

The S/G values may be refered to the soil medium, to groundwater and in a few cases, to

surface water and air. They may also be influenced by the origin of contaminated site

(agricultural or industrial activities), the type of contamination (metals, organic compounds,

etc.), the type of receptors (human, ecosystems, etc.).

As shown in Table 2, most countries are using or intending to use S/G values in the context of

their policies on contaminated lands.


Table 2 : S/G values within the soil policy framework in different countries (Ferguson et al.,

1998)


2.3. Methodologies for risk assessment of contaminated

megasites

2.3.1 Introduction

The economic analysis developed in the WP5 raised several questions among which: What is

the relevant spatial scale for the project? Indeed, groundwater degradation is rarely related to

only one specific source of pollution. In these conditions, it is difficult to prove that a

pollution is due to one site rather than another especially if the site is located in a heavily

industrialized area. This is why it would be interesting in the scope of the FRAC-WECO

project to work on a larger scale than the one of a single site. The megasite scale could be

used.

A megasite is defined as “a large area (indicative size: 5 - 500 km2) with multiple

contaminant sources related to (former) industrial activities, with a significant impact on the

environment, through groundwater, surface water and/or air migration. Due to its complexity

related to site conditions, contaminant characteristics, organization, regulatory aspects and/or

considerable costs, an integrated risk-based management approach is recommended to

manage the risks for the defined receptors” (WELCOME EU project) .

It has been estimated that megasites represent 30 to 50 % of costs associated with the

remediation of contaminated soils and water in Europe. Remediation costs for such sites

amount several billions of euros (WELCOME, 2002).

The complete depollution of contaminated megasites is not an economically and technically

viable solution because of their large extent. An alternative is an approach based on the

management of risk which allows to achieve risks compatible with the use of the site while

maintaining realistic pollution control costs (Béranger and al., 2006).

The management of contaminated megasites has been subject of several studies and national

methodologies. At the European level, projects such as WELCOME and INCORE have

proposed methodologies for the management of contaminated megasites. In the next sections,

these two projects will be described as well as the american point of view with the Superfund

program.


2.3.2 Superfund

Superfund is an environmental program developed in the U.S. during the 80’s. It is addressed

to industrial contaminated megasites.

The Superfund cleanup process may be divided into 9 main steps (US EPA, 2007):

1. Preliminary Assessment (PA)/ Site inspection (SI)�

PA consists in collecting available information about a site and determining whether it poses

little or no threat to human health and to the environment. If the PA results in a

recommendation for further investigation, a Site Inspection is performed. SI studies the nature

of the contaminants and determines if they can be released to the environment and if they

have reached nearby receptors. Based on these results, the site is entered in the NPL Site

Listing Process.

2. National Priorities List (NPL) Site Listing Process

The NPL is the list of U.S. priorities among the known releases or threatened releases of

hazardous substances, pollutants, or contaminants throughout the U.S. and their territories.

3. Remedial investigation (RI)/ Feasability Study (FS)

The remedial investigation/ Feasability Study includes the following steps:

a. Scoping activities�

They begin with the collection of existing site data, including data from previous

investigations. The objectives are to:

� firstly identify boundaries of the study area;

� identify likely remedial action objectives;

� establish whether the site may best be remedied as one or several separate operable

units.

b. Site Characterization

During this phase, samples are taken on field and analysed in laboratory. A baseline risk

assessment is developed to identify the existing or potential risks that may be posed to

human health and to the environment by the site.


c. Development and Screening Alternatives

The objectives of this step are;

� identifying remedial action objectives;

� identifying potential treatment, resource recovery, and containment technologies that

will satisfy these objectives;

� screening the technologies based on their effectiveness, implementability, and cost;

� alternatives can be developed to address contaminated medium, a specific area of the

site, or the entire site.

Once potential alternatives have been developed, it may be necessary to screen out certain

options to reduce the number of alternatives that will be analyzed. The screening process

involves evaluating alternatives with respect to their effectiveness, implementability and

cost.

d. Treatability Investigations�

Treatability investigations are conducted primarily to:

� provide sufficient data to allow treatment alternatives to be fully developed and

evaluated during the detailed analysis phase and to support the remedial design of

selected alternatives;

� reduce cost and performance uncertainties for treatment alternatives to acceptable

levels so that a remedy can be selected.

e. Detailed Analysis

Once sufficient data are available, alternatives are evaluated in detail with respect to

evaluation criteria. The criteria include:

� overall protection of human health and environment;

� long-term effectiveness and permanence;

� reduction of toxicity, mobility, or volume;

� short-term effectiveness;

� implementability;

� cost;


� State acceptance; and

� community acceptance.�

The alternatives are analyzed individually against each criterion and then compared against

one another to determine their respective strengths and weaknesses. The results of the

detailed analysis are summarized so that an appropriate remedy can be selected.

4. Records of Decision (ROD)

The Record of Decision is a public document that explains which cleanup alternatives will be

used to clean up a Superfund site.

5. Remedial Design/ Remedial Action

Remedial Design (RD) is the phase in Superfund site cleanup where the technical

specifications for cleanup remedies and technologies are designed

6. Construction Completion

EPA has developed the construction completions list (CCL) to simplify its system of

categorizing sites and to better communicate the successful completion of cleanup activities

7. Post Construction Completion (PCC)

PCC is to ensure that Superfund response actions provide for the long-term protection of

human health and of the environment. EPA's Post Construction Completion activities also

involve optimizing remedies to increase effectiveness and/or reduce cost without sacrificing

long-term protection of human health and of the environment.

8. National Priorities List Deletion

EPA may delete a final NPL site if it determines that no further response is required to protect

human health or the environment.

9. Site Reuse/ Redevelopment

EPA’s goal is to make sure that at every cleanup site, the Agency and its partners have an

effective process and the necessary tools and information needed to fully explore future uses,

before the cleanup remedy is implemented.

More information is avalaible at: http://www.epa.gov/superfund/


2.3.3 INCORE (INtegrated COncept for groundwater REmediation)

The following paragraphs are taken from the website of the INCORE project:

http://umweltwirtschaft-uw.de/incore/

The purpose of this project is to propose a cost-efficient technical-administrative set of tools

to optimize investigation, evaluation and management of contaminated lands in urban

industrial areas. The proposed INCORE strategy for the investigation, remediation and

revitalisation of industrial areas is based on an integrated quantification of total contaminant

emissions. It considers entire industrial areas instead of particular single sites, in order to

achieve a high level of confidence in the investigation results.

The program is divided into three steps: investigation, assessment and revitalisation. It begins

with the study of the pollution at the megasite scale and ends with the remediation of

individual sources areas or with the containment of plumes. The main advantage of this

approach is that the size of the studied areas decreases stepwise from one cycle to another (see

figure 4).

Figure 4 : INCORE cyclic approach (adapted from INCORE, 2003)

As shown in figure 4, the whole process can be divided in three cycles:

Cycle I: Plume screening

The first step is the gathering of historical data that will allow to define a conceptual model (=

a functional description of the problem). This model will be used to design and perform


Integral Pumping Tests, IPTs (Teutsch and al., 2000). The purpose of the IPTs is to provide

quantitative data about pollution for Cycle II (size of the area affected by contaminated

groundwater and the number and position of potentially contaminated spots).

Cycle II: Source screening

The first objective of cycle II is the identification of the size of the sources with dynamic

investigation using on-site analysis. Then, detailed fingerprinting studies in soil and

groundwater using biomarkers and stable isotopes are used to clarifiy which contaminant

sources are responsible for the identified plumes. The final objective of cycle II is to take

administrative decision on the need for future remediation for each source zone identified.

Cycle III: Source/plume remediation

A feasibility study is firstly performed for site-specific remediation options. It comprises the

evaluation of options for remediation of the source, the plume and integral or combined

source-plume solutions. The most appropriate technology is selected by establishing what

level of contamination reduction is required, considering the future purpose of the site as well

as the profitability of each solution. Finally, the concept of RBLM (Risk Based Land

Management), developed in the scope of the CLARINET project, is used to define the final

rehabilitation scenario.

A detailed flow chart of the INCORE project can be found in annex 3.

2.3.4 WELCOME (Water, Environment and Landscape management at COntaminated

MEgasites)

The following information is taken from the website of the WELCOME project:

http://www.euwelcome.nl/kims/index.php

The WELCOME project was funded by the European Union and was executed from 2002 to

2004. The goal of the project was to develop an Integrated Management Strategy (IMS) for

prevention and reduction of risks at contaminated industrial megasites. This IMS is a stepwise

approach that takes the present situation as a starting point. A risk assessment that takes the

soil-water system and the technical and economic feasilibity of the remediation actions into

account forms the core of this methodology.

The IMS may be divided into 4 main steps: Starting IMS, Risk Assessment, Risk

Management Scenarios, and Implementation.


Starting IMS

The main objective of this section is to provide all criteria needed to define a site as a

megasite and to derive the specific management task.

� decide if the site is a megasite, and if the IMS could be suggested as an appropriate

approach;

� form a group of stakeholders;

� make an overview of boundary conditions;

� make an inventory of megasite information;

� build a conceptual model. Including hypothesis on megasite boundaries and the risk

management zone.

Risk assessment

To assess the risks associated to large-scale groundwater contamination, the IMS provides 5

steps:

� carry out a megasite characterization. This characterization is based on the conceptual

model. It consists in collecting needed data to determine: the contaminant situation,

the megasite natural systems and infrastructure, and the potential receptors;

� define potential risk clusters. A risk-cluster is a geographical subdivision of the risk

management zone with source-pathway-receptor sequences that can be grouped

together into one unit for which risks can be quantified and risk management scenarios

can be developed. Risk clusters form the units on which the megasite risk management

plan will be based;

� carry out fate and transport modelling. It is used for each derived cluster and each

potential receptor to obtain information about the tendency of the temporal and spatial

behaviour of contaminants. The output of this step is detailed determination and

characterization of the contaminants pathways from diverse sources to the receptors

within the defined clusters

� determine risks. Two approaches to assess risks are presented:

� Preliminary assessment of current risks. This procedure is used when a

complete fate and transport modelling is not completed due to e.g. lack of data.


� Comprehensive assessment of current and future risks. This procedure uses the

fate and transport modelling. Based on the modelling results, the receptors at

risk are identified: the emission is quantified in a mass flux predicted to enter -

or a concentration to arrive at -the receptor.

Measured or modelled concentrations need to be compared to receptor specific-

national or European standards. Exceeding values can be assessed as functions of time

and space, and thus risk can be quantified and visualized for each risk cluster.

Site-specific standards are to be derived as a result of the risk assessment, depending

on the following aspects:

� the functions of the receptors of concern

� the potential management scenarios (on a strategic level)

� the stakeholders' priority and risk perception

The standards determined for the receptors of concern serve as the input data for

developing and optimising risk reduction scenarios

� Finalize clustering. The boundaries of the risk management zone are eventually

readjusted according to the results of the risk assessment. After the approval of

stakeholders the evaluation and selection of the risk reduction measures at a cluster

level should be carried out.

Risk Management Scenarios

The objective of this step is to define management scenarios for the megasite that are cost-

effective and sustainable. To achieve it, the following activities need to be done:

� Define the feasibility of management scenario for each cluster. The local situation and

characteristics of the contamination determine whether or not techniques can be

applied in practice.

� Perform cost-efficiency and risk reduction analysis. Scenarios have to be defined in

which it is specified which measures are taken, when, where and to what extent they

affect the contamination (effectiveness). The effectiveness of the scenarios is

determined by risk reduction and costs.

� The stakeholders decide on a final scenario for the entire megasite.


Implementation

The final scenario chosen in the previous step need to be implemented, monitored and

reviewed. The monitoring tends to control the performance of the management scenario. In

the medium and long-term, the performances need to be reviewed and the scenario could

eventually be upgraded if some changes in the system occur.

The WELCOME project provides a set of tools to help the user in the different steps of the

process described above. The interested reader will find the list of these tools in annex 4 and

more information on the website: http://www.euwelcome.nl/kims/tools/index.php

2.3.5 Which megasite approach for FRACO-WECO?

The European approaches briefly described above have advantages and disadvantages.

The approach outlined in the INCORE project offers a way to address the problematic of

major polluted sites by progressively reducing the study area as the process advances.

Conversely, the project does not sufficiently take into account the views of stakeholders. In

addition, the concept of sustainable development is only integrated at the last step of the

approach at the establishment of the RBLM (Béranger and al., 2006).

The approach outlined in the WELCOME project is based on the risk assessment as for the

FRAC-WECO project. The process divided in four steps is clear. Each of them has a specific

objective which allows to choose the adequate final scenario for the remediation of the

megasite. In addition, the information or data collected during the whole project are easily

integrable thanks to the cyclic process of the approach. There are however few points that

should need to be more detailed: the integration of GIS tools, the communications with the

stakeholders and the uncertainty inherent at the different stages of the process are poorly

defined.

Initially, the FRAC-WECO project did not address to the problematic of contaminated

megasites, focusing more on the risks associated with “local” contaminated sites. However,

works performed in WP5, raised the following questions: how to assess specific damages to

groundwater due to one contaminated site or benefits related to its cleanup if the site is part of

an heavily industrial region (pollution plumes migrate within an aquifer and can mix each

other)? If damages arise due to surface water degradation in relation with groundwater

contamination by brownfields, how to assess specific damages due to surface water


degradation related with one specific contaminated site? In summary, from the local site to the

groundwater body level: what is the best scale for an economic analysis as part of FRAC-

WECO project?

The selected test sites (Vilvoorde site1, Chimeuse site and Morlanwelz site

2) belong to

industrialized areas making them far from being the unique potential source of groundwater

contamination. WP5 emphasizes that the best scale to perform the socio-economic analysis on

these sites is the water body scale. However, the resources allocated to the FRAC-WECO

project do not allow to work at the water body scale using a megasite approach such as those

described in the previous sections.

A “megasite” approach that could be used in the project would consist in estimating the part

of the groundwater/surface water pollution due to a contaminated site compared to the whole

groundwater/surface water pollution of the water body. This part can be expressed practically

by a “weight” in any weighted statistics about the groundwater/surface water body.

1 More exactly the « Vilvoorde-Mechelen area» located near the Zenne river (among others)

2 More exactly the ‘Nouveaux Ateliers Mécaniques’ site located in Morlanwelz city (among others)


3. Synthesis of risk assessment tools

3.1. Introduction

The rehabilitation of contaminated sites is a complex process encompassing technological,

environmental and socio-economic aspects. Several billions Euros are spent each year for

remediation of lands affected by contamination. To limit the problems and costs related to the

management of polluted lands, new tools, the Decision Support Tools (DST), have been

widely developed these last years to help the decision-making.

DSTs are interactive softwares used by decision-makers to help answer to questions, solve

problems and support or refute conclusions. They can be incorporated into a structured

decision-making process to identify the choices of management of contaminated sites from a

realistic point of view for environmental site cleanup. DSTs facilitate the use of data, models

and structured decision processes in decision-making.

In the specific case of the FRAC-WECO project, integration of risk analysis models (for

ecosystems and water resources) with socio-economic evaluations is fundamental to

determine the most appropriate decisional process. DSTs have as purpose to define the

different alternatives of effective rehabilitation interventions and efficient remediation

actions, by representing the different decisional scenarios in the modelling tools.

3.2. Literature review of Decision Support Tools

It was estimated in 1999 that there were already more than 500 existing models (risk

assessment/risk management models, exposure assessment/transport/fate models, hazard

identificiation/release assessment models) throughout the world (Fairman & al., 1999).

Nowadays, this number is probably higher than in 1999. Thus, a complete overview of all

these models is an almost impossible task. Therefore, a first selection based on the most cited

models in the literature was performed. In a second step, about thirty softwares were chosen

according to their characteristics and their potential usefulness in the scope of the project. The

criteria that were taken into account in the selection of the softwares are:

• the type of risk concerned (risk on water resources and ecosystems = ecological risk);


• the type of contaminants managed by the software (at least the most common ones:

hydrocarbons, heavy metals, chlorinated solvents and semi-organic volatile

compounds...);

• the type of media managed by the software (soil, groundwater and surface water);

• the possibility to take into account in a certain way the contaminant fluxes data

(hydraulic conductivity, hydraulic gradient, ...);

• the possibility to take into account attenuation factors (partitioning between the liquid-

, solid- and gaseous phases; re-distribution in the soil profile by sorption; dilution in

groundwater; biodegradation);

• the complexity of the models (analytical or numerical);

• the possibility to use GIS data;

• the type of inputs and outputs;

• the possibility to calculate uncertainty on the results;

• the possibility to calculate cost-benefit from remedial action.

Fact sheets on the chosen decision support and modelling tools (DSTs) are presented in

Annex 3 and summarized in Table 3. The information that can be found in Annex 3 mainly

comes from references mentioned in the fact sheets and from the following websites:

• “Federal Remediation Technologies Roundtable” (FRTR):

http://www.frtr.gov/decisionsupport/

• “European Environmental Agency” (EEA):

http://reports.eea.europa.eu/GH-07-97-595-EN-C2/en/iss3c1h.html

• “Risk Assessment for Contaminated Sites in New Zealand" :

http://contamsites.landcareresearch.co.nz/description_of_models.htm

Unfortunately none of the tools presented in Annex 3 meet all the criteria required in the

scope of the project. Though, some of them seem to be more interesting and need to be

studied more in details as shown in Table 3. These are: DESYRE, FIELDS, RBCA, RISC

WORKBENCH and SADA.


Criteria

Softwares

Eco

logy

I/R

Co

nta

min

an

ts

Med

ia

Tra

nsp

ort

da

ta

Att

enu

ati

on

Fa

cto

rs

GIS

Un

cert

ain

ty

Ex

po

sure

eff

ect

Input

Co

st/

Ben

efit

Co

nce

ntr

ati

on

So

il P

rop

erti

es

ABC-TOOL � � � � � � � � � � �

ARAMS � � � � � � � � � � �

CAMEO � � � � � � � � � � �

Chemflo 2000 � � � � � � � � � � �

DESYRE � � � � � � � � � � �

FIELDS � � � � � � � � � �

GeoSEM � � � � ? � � � � � �

Groundwater Sensitivity Toolkit � � � � � � � � � �

GroundwaterFX � ? � � � � � � � �

HSSM � � � � � � � � � �

MassFlux Toolkit � � � � � � � � � �

NAS � � � � � � � � � � �

ON SITE � � � � � � � � � �

PRO UCL � � � � � � � � � �

RAT � � � � � � � � � �

RBCA � � � � � � � � � ?

RESRAD � � � � � � � � � �

RISC WORKBENCH � � � � � � � � � ?

SADA � � � � � � � � � �

SCRIBE � � � � � ?

SERDP � � � � �

SMARTe � � � � � � � � � � �

SOURCE DK � � � � � � � �

VSP � � � � � � � � � � �

Table 3 : Summary of DSTs

Legend:

�Meet the criteria

� �Do not meet the criteria

��

� � Unknown information


3.3. Groundwater modelling

The DSTs described above may be used directly with field data. Though it is sometimes

necessary to have a better understanding of the hydrogeologic conditions of the contaminated

site before using DSTs. This is the reason why more elaborated models allowing to simulate

more precisely groundwater flows and transport of dissolved contaminants will also be used

in the RA process.

The suggested way to proceed with all these tools is the following one :

i. a first RA of the contaminated site using DSTs with avalaible data. This first step

would tend to provide adequate information on the potential risk of the site on

ecosystems and water ressources ;

ii. if it turns out that the site presents a risk for ecosystems and water resources, then it

would be necessary to proceed to the modelling of the groundwater system ;

iii. the results of the groundwater modelling will be used as inputs for new RA

simulations with DSTs.

Three groundwater models have been selected for the project. They must have the ability to

simulate groundwater flows and transport of contaminants in three dimension.

Those models are :

• SUFT3D, developed by ULg-HG, is a 3D numerical model using finite elements and

it allows the modelling of variably saturated groundwater flow and transport

(including adsorption–desorption introduced by a delay factor) from local scale to

catchment scale. In the SUFT3D, it is possible to model flow and transport using

various mathematical approaches with different complexity levels: from a simple

linear reservoir to a detailed spatially distributed approach.

• HydroGeoSPhere, developed by two research groups (University of Laval and

University of Waterloo) under the coordination of Prof. R.Therrien. It is a fully

coupled 3D flow and transport model using advanced numerical finite element

algorithms. These models are currently developed to model specific contaminant

reactions and retardation processes.

• MODFLOW, MODPATH, MT3DMS (MT3D Multi Species) and RT3D via the

interface of GMS (Groundwater Modeling System developed by Environmental

Modelling Research Laboratory). MODFLOW (McDonald & Harbaugh, 1984) is an


extremely versatile finite-difference groundwater flow model. MODPATH (Pollock,

1989) is a particle-tracking model that works with MODFLOW to calculate

groundwater velocities, flow path lines, and advective travel times. MT3D (Zheng,

1990) also works with MODFLOW and calculates concentrations of groundwater

contaminants. It simulates advection, retardation, dispersion, and decay (Fetter, 2001)

. RT3D is a software package for simulating three-dimensional, multispecies, reactive

transport in groundwater.


4. Conclusions and Recommandations

Nowadays, risk assessment (RA) process has become an integrating part in contaminated

lands and natural resources management. This process is based on a causal stress-response

model, commonly called the SPR approach, in which the polluting agent is considered from a

source to a receptor through a known pathway. If one of the main elements of the SPR

approach is missing, the contaminated site does not pose any immediate risk.

The process of risk assessment has however some limitations: the data availability and the

uncertainties on samples, data, models, etc. That is why the process of RA is usually

composed of several steps called tiers. More advanced is the process, larger is the need of data

and more important are the costs. Nevertheless, each new tier leads to a reduction of

uncertainties.

Currently, there are no universal methodologies and tools for site screening and risk assessment,

due to specificities of each site and situation as well as political, social and environmental

contexts of each country or region. However, many countries have based their environmental

policy on the U.S. one which includes five main steps: problem formulation, hazard

identification, characterization of exposure, dose- response and risk characterization.

In industrialized areas, it is sometimes difficult to attribute the observed pollution to a single

site as there are lots of pollution sources. It is therefore interesting to consider the

contaminated area as a whole, what is called the “megasite”. Several management

methodologies of contaminated megasites have been reviewed in this deliverable. For the

FRAC-WECO project, it is suggested (WP5) to work at the water body scale to perform the

socio-economic analysis. At this scale and with the avalaibe resources, the project will tend to

estimate the relative weight of the groundwater/surface water pollution due to a contaminated

site compared to the whole groundwater/surface water pollution of the water body.

Among the objectives of the FRAC-WECO project, the development and the validation of site

screening and risk assessment tools are key steps. In this perspective, an important review of

risk assessment and modelling tools used as decision support has been performed. First, the most

cited in the literature have been selected and then classified in terms of general criteria such as:

type of risk concerned, type of contaminants, parameters to introduce/input, calculation of


uncertainty, etc. This classification allows therefore to identify the advantages and drawbacks

of each tool , with respect to the objectives of the project.

From this review, five of the most relevant modelling tools have been selected. They will be

analyzed more in detail and tested on the selected contaminated sites as part of the project.

Thereafter, a comparison of the results will be performed and will be subject to the next

deliverable D.4.1 “Comparison and validation of risk assessment tools”.


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Annexes


Annex 1: Definitions

Definition of some words necessary for the good understanding of the risk assessment

concept.

Analysis The analytical phase of the risk assessment in which the

potential for adverse effects are calculated based on the

hazard identification, dose-response assessment, and the

exposure assessment.

Assessment endpoint Functions or characteristics of a group or population of people

or organisms (such as reproduction, growth, and lack of

disease) that can be measured in relation to the intensity or

concentration of a stressor.

Conceptual model A diagram or written description of the predicted key

relationships between the stressor(s) and the assessment

endpoint(s) for a risk assessment

Ecological Risk Assessment Ecological risk assessment is the process of estimating the

potential impact of a chemical or physical agent on a human

population under a specific set of conditions

Ecosystem An area of nature including living organisms and non-living

substances interacting to produce an exchange of material

between the living and non-living parts. The term ecosystem

implies interdependence between the organisms comprising

the system.

Environmental Impact

Assessment An assessment required by the National Environmental Policy

Act to evaluate fully potential environmental effects

associated with proposed federal actions.

Exposure Contact with a chemical, physical or biological agent.

Exposure Assessment The estimation (qualitative or quantitative) of the magnitude,

frequency, duration, route and extent of exposure to a

chemical substance or contaminant.

Hazard The capacity to produce a particular type of adverse health or

environmental effect, e.g. one hazard associated with benzene


is leukemia.

Health Risk Assessment Health risk assessment is the process of estimating the

potential impact of a chemical or physical agent on a human

population under a specific set of conditions.

Integrated Risk Assessment A process that combines risks from multiple sources,

stressors, and routes of exposure for humans, biota and

ecological resources in one assessment with a defined point of

focus (See also cumulative risk assessment).

Megasite Is a large area (indicative size: 5 - 500 km2) with multiple

contaminant sources related to (former) industrial activities,

with a significant impact on the environment, through

groundwater, surface water and/or air migration. Due to its

complexity related to site conditions, contaminant

characteristics, organization, regulatory aspects and/or

considerable costs, an integrated risk-based management

approach is recommended to manage the risks for the defined

receptors

Receptor An organism, plant, human or physical structure which may

be exposed to a chemical or other hazardous agent.

Risk Management The process of evaluating alternative actions and selecting

options in response to risk assessments. The decision making

may incorporate scientific, social, economic and political

information. The process requires value judgements, e.g. on

the tolerability of risk and the reasonableness of costs.

Source An entity or action that releases to the environment or

imposes on the environment chemical, biological, or physical

stressor or stressors.

Toxicity The quality or degree of being poisonous or harmful to plant,

animal, human or other life.


Annex 2: International approaches to ecological risk

assessment


Annex 3: INCORE flow chart (adapted from INCORE, 2003)


Annex 4: Tools developed in the scope of The WELCOME project

(adapted from Béranger and al., 2006)

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Annex 5: Fact sheets on the decision support and modelling

tools


ACRONYM ABC-TOOL

Complete title Assessment of Benefits and Costs of remedial actions

Author(s) Netherlands Organisation for Applied Scientific Research-

TNO

Website/References http://www.euwelcome.nl/kims/tools/index.php?index=110

Description/Functionalities

ABC-TOOL is a decisional and economical tool allowing identifying and

examining the feasibility of different remediation techniques. It consists of

three modules:

(1) Assessment: determination of the feasibility of remediation techniques

for a specific site;

(2) Benefits: determination of environmental load and merit of techniques;

(3) Costs: evaluation of costs per technique and per country.

Comments

ABC-TOOL is used according to some conditions:

Type of contaminants Media

Hydrocarbons

Chlorinated solvents

Metals

Heterogeneous

sand/clay/loam/peat

Homogeneous sand

Homogeneous clay

It considers the groundwater flow velocity as a main criterion for the

choice of the remediation technique.


ACRONYM ARAMS

Complete title Adaptive Risk Assessment Modeling System

Author(s) U.S. Army Engineer Research and Development Center

(ERDC) and U.S. Army Center for Health Promotion and

Preventive Medicine (USACHPPM)

Website/References http://el.erdc.usace.army.mil/arams/


ARAMS is an analysis software with wide database and modeling tools

used to describe the pollutant source and to integrate media fate and

transport, exposure pathways, intake and uptake, and effects/impacts of

contaminants into a conceptual site model (CSM) framework. It includes:

� Analytical modeling;

� Uncertainty analysis;

� Statistical analysis;

� Conceptual site model;

� Human health risk assessment;

� Ecological risk assessment.

Comments

ARAMS is used according to some conditions:



Metals

Semi-volatile organic compounds

Pesticides/PCBs

Hydrocarbons

Radionuclides

Soil sediment

Air

Surface water

Groundwater

The chemical reactivity of pollutants is not considered in the software. The

GIS tool is still not fully working.


ACRONYM CAMEO

Complete title Computer-Aided Management Of Emergency Operations

Author(s)

U.S. Environmental Protection Agency Office of

Emergency Management (OEM) and the National Oceanic

and Atmospheric Administration Office of Response and

Restoration (NOAA)

Website/References http://www.epa.gov/emergencies/content/cameo/index.htm


CAMEO is a decision support tool used to plan for and respond to

chemical emergencies. It includes:


� Database;

� Chemical reactivity analysis;

� Emergency response tool;

� Regulatory reporting.

Comments

CAMEO is used according to some conditions:



Metals


Hydrocarbons

Radionuclides

Soil sediment

Soil gas

Air

Surface water

Groundwater

The study on the fate and transport of contaminant, the exposure pathways

and impacts on the ecosystems are not included in this tool.


ACRONYM CHEMFLO 2000

Complete title Chemflo 2000

Author(s) D.L. Nofziger and Jinquan Wu

Website/References http://soilphysics.okstate.edu/software/chemflo/


Chemflo 2000 was developed to simulate water movement and fate and

transport of contaminants in unsaturated media. It includes:

� Numerical modeling;

� Sensitivity analysis.

Comments

CHEMFLO 2000 is used according to some conditions:


All Soil

Groundwater

The models used by CHEMFLO 2000 assume a strictly one-dimensional

flow and transport in the soil and constant soil hydraulic properties.


ACRONYM DESYRE

Complete titleDEcision Support sYstem for REhabilitation of contaminated

sites

Author(s)

Venice Research Consortium in collaboration with the

University of Venice, Ca’ Foscari (Dep. of Environmental

Sciences and Mathematics), Thetis Spa and CNR-ISE.

Website/References http://venus.unive.it/eraunit/research_group_projects.htm#desyre


DESYRE is a very sophisticated tool integrating environmental and

technological databases, risk assessment models, and multi-criteria

procedures. It includes:


� Geographic information system (GIS);


� Remediation tool.

DESYRE is composed of five modules: (1) characterisation – collect of

information about the contaminated site, (2) risk – development of models

for the analysis of fate, transport and exposure, (3) socio-economical –

evaluation of constraints and benefits, (4) technological analysis –

evaluation of the feasibility, advantages, limits and costs of remediation

techniques, and (5) decision.

Comments

DESYRE is used according to some conditions:


All All

DESYRE allows performing pre and post remediation spatial risk

assessment for human health. The ecological risk assessment is currently in

process.


ACRONYM FIELDS Tools for ArcGIS©

Complete title FIELDS Tools for ArcGIS©

Author(s) EPA Region 5 FIELDS Team

Website/References http://epa.instepsoftware.com/fields/


FIELDS Tools for ArcGIS is a tool for data analysis and interpretation for

environmental decision-making. It allows evaluating the extent of

contamination and “hot spot” sizes, estimating risks for human health and

environment, prioritizing site goals and weighing potential actions. It

includes:


� Database (includes a query tool);

� Sample design;

� Geospatial modeling and analysis;

� Ecological risk assessment;


� Cost/benefits analysis;

� Remedial tools.

Comments

FIELDS is used according to some conditions:



Metals


Pesticides/PCBs

Hydrocarbons

Radionuclides

Soil sediment

Soil gas

Surface water

Groundwater

FIELDS tends to provide the required information for Tier 2 (complex

models for fate and transport of contaminants).


ACRONYM GEOSEM

Complete title GEOSpatial Exposure Model

Author(s) SRC (Syracuse Research Corporation)

Website/References http://esc.syrres.com/geosem/default.htm


GEOSEM is a program for incorporating spatial statistics in human health

and ecological exposure assessment. It includes:



� Visualization;



� Geospatial interpolation.

Comments

GEOSEM is used according to some conditions:



Metals


Pesticides/PCBs

Hydrocarbons

Radionuclides

Soil sediment

Soil gas

Surface water

Groundwater


ACRONYM GroundwaterFX

Complete title GroundwaterFX

Author(s) DecisionFX

Website/References http://www.decisionfx.com/GWFX.html


GroundwaterFX is a decision support tool that provides information

regarding the necessary number and location of monitor wells to delineate

the nature and extent of a contaminant plume. It also provides visual

feedback on the nature and extent of the contamination. Groundwater FX :

� Utilizes flow and transport models in a probabilistic framework to

account for uncertainty in contaminant movement ;

� Decision support tool to optimize the number and placement of

monitor wells to delineate the nature and extent of a contaminant

plume ;

� Utilizes optimization theory to minimize the number and cost of

monitor wells and boreholes for sampling locations ;

� Simplifies the analysis of natural attenuation potential.

Comments

GroundwaterFX is used according to some conditions:


Not mentioned Groundwater


ACRONYM Groundwater Sensitivity Toolkit

Complete title Groundwater Sensitivity Toolkit

Author(s) GSI Environmental Inc.

Website/References http://www.gsi-net.com/Software/GroundwaterSensitivity.asp


Groundwater Sensitivity Toolkit was developed to evaluate the sensitivity

of groundwater resource to a potential release of contaminants at a

particular site. It includes a site screening tool.

Comments

Groundwater Sensitivity Toolkit is used according to some conditions:



Metals

Hydrocarbons

Groundwater


ACRONYM HSSM

Complete title Hydrocarbon Spill Screening Model

Author(s)

Robert S. Kerr Environmental Research Laboratory

Office of Research and Development U.S. Environmental

Protection Agency

Website/References http://www.epa.gov/ada/csmos/models/hssmwin.html


HSSM has as objectives to simulate releases of light non aqueous phase

liquids (LNAPLs) to the subsurface environment and to estimate the

impacts of pollutants on the aquifers. It includes:


� Visualization;

� Screening tool.

Comments

HSSM is used according to some conditions:



Hydrocarbons

Soil sediment

Groundwater

HSSM may be used to give a rough estimation of pollutants concentrations

in groundwater.

The discretization of flow domain and the techniques of iterative solution

are not integrated in the software.


ACRONYM MASSFLUX TOOLKIT

Complete title Mass Flux Toolkit


Website/References http://www.gsi-net.com/Software/massfluxtoolkit.asp


Mass Flux Toolkit is a tool focused on different mass flux approaches. It

allows calculating mass flux from transect data and applying mass flux

values to manage groundwater plumes for various pollutants. It includes:


� Module for the calculation of the total mass flux across one or more

transects of a plume;

� Uncertainty analysis on the calculation of mass flux;

� Module for critical dilution calculations for plumes.

Comments

Mass Flux Toolkit is used according to some conditions:



Metals


Pesticides/PCBs

Hydrocarbons

Radionuclides

Groundwater

It provides information about effects of remediation/impacts of natural

attenuation processes.


ACRONYM NAS

Complete title Natural Attenuation Software

Author(s)

Southern Division, Naval Facilities Engineering

Command (NAVFAC) and Naval Facilities Engineering

Service Center (NFESC)

Website/References http://www.nas.cee.vt.edu/index.php


NAS is a graphical user interface in order to estimate the time required to

achieve site-specific goals at contaminated sites. It includes:



� Visualization;

� Remedial process selection.

Comments

NAS is used according to some conditions:



Metals


Hydrocarbons

Radionuclides

Groundwater

NAS is designed for an application in groundwater with a relatively

homogeneous and saturated porous media, and assumes that groundwater

flow is uniform and uni-directional.


ACRONYM ONSITE

Complete title On Site

Author(s)

National Exposure Research Laboratory Office of

Research and Development U.S. Environmental

Protection Agency

Website/References http://www.epa.gov/athens/onsite


On Site was developed to evaluate transport of contaminants in the

subsurface. It includes:


� Sensitivity analysis.

Comments

On Site is used according to some conditions:



Metals


Pesticides/PCBs

Hydrocarbons

Radionuclides

Soil sediment

Air

Surface water

Groundwater

On Site includes contaminant fate and transport in one dimension.


ACRONYM PRO UCL

Complete title Upper Confidence Limit

Author(s) EPA Technical Support Center (TSC)

Website/References http://www.epa.gov/esd/tsc/software.htm


PRO UCL is software to support risk assessment and cleanup decisions at

contaminated sites. It estimates the 95 percent upper confidence limit

(UCL) of an unknown population mean of environmental data sets. It

includes a statistical analysis.

• Estimate the exposure point concentration (EPC) term,

• Determine the attainment of cleanup standards,

• Estimate background level mean contaminant concentrations, or

• Compare the soil concentrations with site specific soil screening

levels.

Comments

PRO UCL is used according to some conditions:



Metals


Pesticides/PCBs

Hydrocarbons

Radionuclides

Soil sediment

Air

Surface water

Groundwater

PRO UCL is often used to estimate the exposure point concentration, to

support risk assessment applications, to determine the attainment of

cleanup standards, to estimate the background level mean contaminant

concentrations and to compare the soil mean concentrations with site-

specific soil screening levels.


ACRONYM RAT

Complete title Rapid Assessment Tool

Author(s) EPA Region 5 FIELDS Team

Website/References http://epa.instepsoftware.com/rat/


RAT is a Microsoft Windows based software package facilitating field data

collection in real-time. It includes:

� Visualization;

� Data acquisition;

� Data management.

Comments

RAT is used according to some conditions:



Metals


Hydrocarbons

Radionuclides

Soil sediment

Air


ACRONYM RBCA TOOLKIT

Complete title Risk Based Corrective Action

Author(s)

RBCA Framework (American Society for Testing and

Materials) and RBCA Tool Kit (Groundwater Services Inc.,

USA)

Website/References http://www.groundwatersoftware.com/rbca_tool_kit.htm


The RBCA Toolkit is a management approach used to assess

actual/possible human and environmental risks caused by exposure to

chemical releases. It also helps to determine appropriate remedial actions

in response to such releases. It includes:


� Deterministic modeling;

� Natural attenuation modeling;

� Reactional analysis of contaminants;

� Transient modeling options;

� Possibility to insert dilution/delay factor to concentrations values.

Comments

RBCA Toolkit is used according to some conditions:



Metals


Hydrocarbons

Radionuclides

All

The uncertainty analysis is not incorporated in RBCA Toolkit. Moreover, it

is not able to simulate contaminant concentrations down-gradient of a

discharge point for surface water.


ACRONYM RESRAD

Complete title RESidual RADioactivity

Author(s) Environmental Assessment Division Argonne National

Laboratory United States Department of Energy

Website/References http://web.ead.anl.gov/resrad/home2/


RESRAD is a code developed to assess risks posed by radioactively

contaminated sites on human and environment. It includes:





� Sensitivity analysis;

� Cost/benefits analysis.

Comments

RESRAD is used according to some conditions:


Radionuclides

Soil sediment

Air

Surface water

Groundwater

RESRAD assists in developing cleanup criteria.


ACRONYM RISC WorkBench

Complete title Risc WorkBench

Author(s) Scientific Software Group

Website/References http://www.scientificsoftwaregroup.com/pages


RISC WorkBench is software package used to perform fate and transport

modeling and human health/ecological risk assessments for contaminated

sites. It is based on the standard procedures outlined in the U.S EPA's Risk

Assessment Guidance for Superfund (U.S EPA, 1989) in order to calculate

exposure assessment, toxicity assessment and risk assessment. It includes:




� Deterministic modeling;

� Stochastic modeling.

Comments

RISC WorkBench is used according to some conditions:



Metals


Pesticides/PCBs

Hydrocarbons

Radionuclides

Soil sediment

Surface water

Groundwater

The ecological risk assessment is principally focused on the water quality.


ACRONYM SADA

Complete title Spatial Analysis and Decision Assistance

Author(s)

The United States Environmental Protection Agency

(Region 5 FIELDS Group) and The United States Nuclear

Regulatory Commission (NRC)

Website/References http://www.tiem.utk.edu/~sada/index.shtml


SADA is a complete tool performing environmental assessments in support

of decision-making. It includes:



� Data exploration and visualization;





� Sample plan design;

� Cost/benefit analysis;

� Geospatial interpolation.

Comments

SADA is used according to some conditions:



Metals


Pesticides/PCBs

Hydrocarbons

Radionuclides

Soil sediment

Soil gas

Surface water

Groundwater


ACRONYM SCRIBE

Complete title SCRIBE

Author(s) U.S. Environmental Protection Agency Environmental

Response Team (ERT)

Website/References http://www.ertsupport.org/scribe_home.htm


Scribe is a software tool developed to assist in the process of managing

environmental data (Tier 1). It includes:

� Data acquisition;

� Monitoring field data;

� Form/Label generation;

� Database.

Comments

SCRIBE is used according to some conditions:



Metals


Pesticides/PCBs

Hydrocarbons

Radionuclides

Soil sediment

Air

Surface water

Groundwater


ACRONYM SERDP

Complete title Source Depletion Decision Support System


Website/References http://www.gsi-net.com/Software/serdp_dss.asp


SERDP is a program used to help the decision-making process for

remediation of dense non aqueous phase liquid (DNAPLs) source zones. It

includes:

� Visualization;

� Data filtering;

� Review research.

Comments

SERDP is used according to some conditions:


DNAPL Groundwater


ACRONYM SMARTe

Complete titleSustainable Management Approaches and Revitalization

Tools - electronic

Author(s)

U.S. Environmental Protection Agency Office of

Research and Development and Office of Brownfields

Cleanup and Redevelopment

Website/References http://www.smarte.org/smarte/home/index.xml


SMARTe is decision support system used to develop and to evaluate future

re-use scenarios for potentially contaminated lands (Tier 3). SMARTe

integrates analysis tools concerning all aspects of the revitalization process

including:

� Planning;

� Environmental aspect;

� Economic aspect;

� Social aspect.

Comments

SMARTE is still under developed about land-use options analysis,

economic analysis calculators, environmental management tools, etc.


ACRONYM SOURCE DK

Complete title Source DK


Website/References http://www.gsi-net.com/Software/SourceDK.asp


SourceDK is used to develop a screening-level model in order to estimate

groundwater remediation timeframes and to associate uncertainties at sites

where groundwater is contaminated by a source in the unsaturated zone. It

includes:



� Chemical reactivity analysis (only biodegradation);

� Remedial process selection.

Comments

Source DK is used according to some conditions:




Pesticides/PCBs

Hydrocarbons

Groundwater

Source DK is not designed to simulate the effects of chemical diffusion.

It also assumes that all the biodegradation occurs in the dissolved phase

and acts only on dissolved constituents.

Source DK is primarily geared for natural attenuation processes.


ACRONYM VSP

Complete title Visual Sample Plan

Author(s) Pacific Northwest National Laboratory

Website/References http://dqo.pnl.gov/vsp/


VSP provides statistical solutions to sampling design problems. It helps the

user to select the correct number and location of samples to achieve a

certain confidence level in the decision-making. It includes:

� Visualization;

� Initial sampling;

� Secondary sampling;


� Cost/benefit analysis.

Comments

VSP is used according to some conditions:



Metals


Pesticides/PCBs

Hydrocarbons

Radionuclides

Groundwater

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